JP4587302B2 - Antibacterial products for doctors - Google Patents

Description

The present invention relates to a medical antibacterial product having a carbon-doped titanium oxide surface layer. More specifically, the first invention relates to a carbon-doped titanium oxide layer in which carbon is doped in a Ti-C bond state. (Hereinafter referred to as a carbon-doped titanium oxide layer), which has excellent durability (high hardness, scratch resistance, abrasion resistance, chemical resistance, heat resistance) and functions as a visible light responsive photocatalyst The present invention relates to antibacterial products for doctors having a titanium layer.
In addition, since the second invention has a large number of protrusions made of titanium oxide or titanium alloy oxide on at least a part of the surface portion, it can easily adsorb volatile organic compounds (VOC) and has a large surface area. In addition, carbon-doped titanium oxide has high activity as a photocatalyst because it is carbon-doped, functions as a visible light responsive photocatalyst, has high hardness, and has excellent peel resistance, wear resistance, chemical resistance, and heat resistance. The present invention relates to antibacterial products for physicians having a layer.

  In recent years, many researches have been carried out in many technical fields for the practical application of photocatalysts. As a result of the photocatalyst's sterilization, deodorization and antifouling functions and its super hydrophilicity, nosocomial infections etc. In addition to antibacterial tiles for the purpose of prevention, antibacterial products such as antibacterial containers and scalpels have been developed.

Conventionally, titanium dioxide TiO ₂ (simply referred to as titanium oxide in the present specification and claims) is known as a substance exhibiting a photocatalytic function. As a method of forming a titanium oxide film on titanium metal, since the 1970s, a method of forming a titanium oxide film on titanium metal by anodic oxidation, thermal titanium oxide on a titanium metal plate in an electric furnace supplied with oxygen A method of forming a film, a method of forming a titanium oxide film on titanium metal by heating a titanium plate in a flame of city gas at 1100 to 1400 ° C. are known (see Non-Patent Document 1).

  When manufacturing photocatalyst products that can provide deodorant, antibacterial, anti-fogging and antifouling effects by such photocatalytic function, titanium oxide sol is generally applied to the substrate by spray coating, spin coating, dipping, etc. (For example, refer to Patent Documents 1 to 3). In addition, the method of forming a photocatalyst film | membrane by sputtering method is also known (for example, refer patent documents 4-5).

  Further, in order to make titanium oxide function as a photocatalyst, ultraviolet rays having a wavelength of 400 nm or less are necessary. However, many studies of titanium oxide photocatalysts that function by visible light by doping various elements have been conducted. For example, comparing titanium oxides doped with F, N, C, S, P, Ni, etc., there is a report that nitrogen-doped titanium oxide is superior as a visible light responsive photocatalyst (see Non-Patent Document 2). .

As described above, titanium oxide photocatalysts doped with other elements include titanium compounds in which oxygen sites of titanium oxide are replaced with atoms such as nitrogen, and titanium formed by doping atoms such as nitrogen between lattices of titanium oxide crystals. A photocatalyst composed of a compound or a titanium compound in which atoms such as nitrogen are arranged at grain boundaries of a polycrystalline aggregate of titanium oxide crystals has been proposed (see, for example, Patent Documents 6 to 9). Further, for example, n-TiO ₂ -xCx, which is a chemically modified titanium oxide, is obtained by applying a natural gas combustion flame in which the temperature of the combustion flame is maintained at around 850 ° C. by adjusting the flow rates of natural gas and oxygen to titanium metal. There is a report that this absorbs light of 535 nm or less (see Non-Patent Document 3).

Furthermore, crystal nuclei prepared by various production methods such as CVD or PVD are put into a sol solution composed of an inorganic metal compound or an organometallic compound, or a sol solution is applied to the crystal nuclei, solidified, and heat-treated. It is known that a highly active photocatalytic function can be obtained by growing a titanium oxide crystal from the crystal nucleus, whereby the crystal shape of the titanium oxide crystal grown from the crystal nucleus forms a columnar crystal (for example, Patent References 10 to 12).
JP 09-2441038 A Japanese Patent Application Laid-Open No. 09-262481 Japanese Patent Laid-Open No. 10-053437 JP-A-11-012720 JP 2001-205105 A JP 2001-205103 A (Claims) JP 2001-205094 A (Claims) JP 2002-95976 A (Claims) WO 01/10553 pamphlet (claims) JP 2002-253975 A JP 2002-370027 A JP 2002-370034 A A. Fujishima et al., J. Electrochem. Soc. Vol. 122, No. 11, p. 1487-1489, November 1975 R. Asahi et al., SCIENCE Vol. 293, July 13, 2001, p. 269-271 Shahed UM Khan et al., SCIENCE Vol. 297, September 27, 2002, p. 2243-2245

However, by applying the above-mentioned titanium oxide sol onto the substrate by spray coating, spin coating, dipping, etc., or by applying a titanium oxide film formed by sputtering or a natural gas combustion flame to titanium metal The film of n-TiO _2-X Cx, which is a chemically modified titanium oxide film, has insufficient hardness and durability, so when it is applied to a product for doctors, it can be used as a photocatalyst by repeated washing or use over time. Peeling and abrasion are likely to occur, and it has been difficult to use this for a long period of time while maintaining the action of sterilization, antibacterial, deodorant, etc. by the photocatalyst and super hydrophilicity.

  In addition, when sterilizing and cleaning operating room flooring using acid, conventional photocatalysts are prone to deterioration of the binder, so the life of antibacterial products for doctors such as photocatalyst peeling and flooring is shortened. There was also a problem of becoming. Furthermore, sterilization using the same disinfectant has a risk of causing resistant bacteria.

In addition, when a titanium oxide crystal is grown from the crystal nucleus so that the crystal shape of the titanium oxide crystal grown from the crystal nucleus forms a columnar crystal, a highly active photocatalytic function can be obtained. Since the columnar crystals only grow from the seed crystals placed on the substrate, the adhesion strength of the formed columnar crystals to the substrate was not sufficient. Therefore, the produced photocatalyst is not always satisfactory in terms of durability such as wear resistance.

  The present invention has been made to solve such problems, and the first object thereof is to function as a visible light responsive photocatalyst and has high photocatalytic activity, such as sterilization, sterilization, deodorization, and antifouling. For physicians equipped with a carbon-doped titanium oxide layer with excellent function and super hydrophilicity, high film hardness, and excellent durability (peeling resistance, abrasion resistance, chemical resistance, heat resistance, corrosion resistance) To provide antibacterial products.

  The second object of the present invention is that VOC can be easily adsorbed, has a large surface area and is carbon-doped, and therefore has high activity as a photocatalyst and functions as a visible light responsive photocatalyst. The object is to provide an antibacterial product for doctors equipped with a carbon-doped titanium oxide layer excellent in chemical resistance and heat resistance.

As a result of intensive studies to achieve the above-mentioned object, the present inventor heat-treats the surface of a substrate whose surface layer is made of titanium or a titanium alloy at a high temperature using a combustion flame of a gas containing hydrocarbon as a main component. As a result, carbon is doped in a Ti-C bond state, and has excellent durability (high hardness, scratch resistance, abrasion resistance, chemical resistance, heat resistance) and functions as a visible light responsive photocatalyst. The present inventors have found that a member useful for application to a medical product having a carbon-doped titanium oxide layer as a surface layer (hereinafter referred to as “multifunctional material”) can be obtained.

That is, the first antibacterial product for doctors of the present invention has at least a surface layer comprising a carbon-doped titanium oxide layer, the carbon is doped in a Ti-C bond state, and has excellent durability and a visible light response type. It is formed of a multifunctional material (first multifunctional material) that functions as a photocatalyst.
In particular, as a result of intensive studies to achieve the above object, the present inventor has found that a combustion flame of unsaturated hydrocarbon, particularly acetylene, is directly applied to the surface of a substrate whose surface layer is made of titanium or a titanium alloy under specific conditions. Or by heating the surface of the substrate in a combustion exhaust gas atmosphere of an unsaturated hydrocarbon, particularly acetylene, under specific conditions, and the surface layer is made of titanium oxide or a titanium alloy oxide. A layer in which fine columns are erected is formed, and the layer in which the fine columns are erected is cut in a direction along the surface layer so that at least a part of the titanium oxide or titanium alloy oxide is formed on the substrate. A member in which a layer in which a fine pillar made of is exposed is exposed, a large number of continuous narrow protrusions made of titanium oxide or titanium alloy oxide on a thin film, and a minute in which a forest stands on the protrusion That both of them have a large number of protrusions made of titanium oxide or titanium alloy oxide on at least a part of the surface, both of which are useful multi-functions It is a material, and fine pillars, which are protrusions made of titanium oxide or titanium alloy oxide, and continuous narrow protrusions are carbon-doped, so it has high photocatalytic activity and functions as a visible light responsive photocatalyst. Furthermore, the inventors have found that a multi-functional material that can easily adsorb VOC, has high hardness, and is excellent in peel resistance, wear resistance, chemical resistance, and heat resistance has been obtained, and the present invention has been completed.

  That is, the second antibacterial product for doctors of the present invention has a large number of protrusions made of titanium oxide or titanium alloy oxide on at least a part of the surface, for example, titanium oxide or at least part of the surface. A layer in which fine columns made of titanium alloy oxide are forested is exposed, or a large number of continuous narrow projections made of titanium oxide or titanium alloy oxide on a thin film and forested on the projections The fine pillars are exposed, and the protrusions, for example, the fine pillars and the narrow protrusions are formed of a carbon-doped multifunctional material (second multifunctional material).

  In the present invention, at least a part of various instruments (product for doctors) used in the medical industry is formed of the first multifunctional material or the second multifunctional material.

According to the multifunctional material used in the first invention, a carbon-doped titanium oxide layer doped with carbon in a Ti—C bond state is formed on the surface layer of the base of the antibacterial product for doctors. Effectively functions as a highly active visible light responsive photocatalyst that responds to wavelengths of 400 nm or more, and exhibits sterilization, antibacterial, deodorant, antifouling, etc. due to the organic matter decomposition function, as well as superhydrophilic contamination. Ease of removal can be achieved. In addition, the formed carbon-doped titanium oxide layer is extremely hard and has excellent durability (peeling resistance, abrasion resistance, chemical resistance, heat resistance, corrosion resistance). An antibacterial product for doctors that can be used over a long period of time while maintaining its action and super hydrophilicity is provided. Moreover, according to this multifunctional material, this can be applied to various medical products for which hard chrome plating has been conventionally used. In addition, it can be expected to be applied to antibacterial products for doctors for the purpose of reducing the potential of the base material to prevent pitting corrosion, overall corrosion, stress corrosion cracking, and the like. Furthermore, since this multifunctional material is extremely hard, if it is applied to the teeth of scalpels, saws, or scissors, it can provide antibacterial products for doctors that are excellent in sharpness and hard to dull. .
In the present invention, since no binder is used, even when a medical product is washed with an acid or the like, the service life of the product is not shortened due to deterioration of the binder. Moreover, according to the sterilization by the photocatalyst, there is no fear of producing resistant bacteria unlike the sterilization by the disinfectant, and it becomes possible to effectively prevent nosocomial infections and the like.

  Further, according to the multifunctional material used in the second invention, in addition to the above effects, the photocatalytic activity is very high even under visible light (that is, normal visible light illumination), and it is effective for sterilization, antibacterial, deodorization and the like. A highly durable antibacterial product for doctors that is superior and that can easily absorb VOCs is also provided.

In addition, after washing antibacterial products for doctors with carbon-doped titanium oxide surface layer, sterilization by irradiating with ultraviolet rays facilitates cleaning of dirt due to the superhydrophilicity of the photocatalyst, and sterilization of ultraviolet rays and photocatalysts Due to the synergistic effect of action, antibacterial products for physicians can be more effectively disinfected than before.
Furthermore, if washing is performed while irradiating ultraviolet rays or visible light, the superhydrophilicity is further enhanced, and washing can be further facilitated.

The present invention is mainly used in hospitals such as medical waste treatment devices and various medical tables, as well as instruments such as surgical scalpels, forceps, scissors, and saws, various containers such as medicine containers, and excised organ storage boxes. In addition to antibacterial metal products, it can be applied to operating room tiles, wall materials, sinks, etc. In other words, if the purpose is to improve the sterilization, antibacterial, deodorizing, etc. of the visible light responsive photocatalyst and to prevent the occurrence of nosocomial infections, it can be applied to various medical products. it can.
The present invention realizes the high durability of the photocatalyst and the product itself, which cannot be said to be sufficient with the conventional photocatalyst (first invention), and further exhibits the effects of high sterilization / antibacterial / deodorization (second Invention).

The antibacterial product for doctors of the first invention is manufactured by heat-treating at least a surface of a substrate whose surface layer is made of titanium or a titanium alloy at a high temperature using, for example, a combustion flame of a gas mainly containing hydrocarbons. However, the substrate of which at least the surface layer is made of titanium or a titanium alloy may be formed of the surface portion forming layer and the core material even if the substrate is entirely made of titanium or a titanium alloy. And their materials may be different. In addition, the shape of the substrate is a final product that has sterilization, antibacterial, deodorant, etc., and durability such as high hardness, scratch resistance, abrasion resistance, chemical resistance, and heat resistance. It may be the shape (flat or three-dimensional) or the final product shape that is desired to have a visible light responsive photocatalytic function on the surface, and the carbon-doped titanium oxide layer formed on the surface is cut or ground in the processing process. The shape may be a material as long as it is not removed by, for example.

If at least the surface layer is made of titanium or a titanium alloy and the surface portion forming layer and the core material are made of different materials, the thickness of the surface portion forming layer is the carbon-doped oxidation formed. It may be the same as the thickness of the titanium layer (that is, the entire surface portion forming layer becomes a carbon-doped titanium oxide layer) or may be thick (that is, a portion of the surface portion forming layer in the thickness direction is carbon-doped oxidized. It becomes a titanium layer and a part remains as it is). The material of the core material is not particularly limited as long as it does not burn, melt or deform during the heat treatment in the manufacturing method of the first invention. For example, iron, iron alloy, non-ferrous alloy, ceramics, other ceramics, high temperature heat resistant glass, etc. can be used as the core material. As a substrate composed of such a thin film surface layer and a core material, for example, a film made of titanium or a titanium alloy on the surface of the core material by a method such as sputtering, vapor deposition or thermal spraying, or a commercially available one The titanium oxide sol may be applied to the surface of the core material by spray coating, spin coating or dipping to form a film.

Further, the antibacterial product for medical doctors of the first invention is composed of a layer made of carbon-doped titanium oxide or titanium alloy oxide, an intermediate layer, and a core material, and the intermediate layer is titanium or titanium alloy, The core material may be made of a material other than titanium or a titanium alloy.

Various known titanium alloys can be used as the titanium alloy, and are not particularly limited. For example, Ti-6Al-4V, Ti-6Al-6V-2Sn, Ti-6Al-2Sn-4Zr-6Mo, Ti-10V-2Fe-3Al, Ti-7Al-4Mo, Ti-5Al-2.5Sn, Ti- 6Al-5Zr-0.5Mo-0.2Si, Ti-5.5Al-3.5Sn-3Zr-0.3Mo-1Nb-0.3Si, Ti-8Al-1Mo-1V
Ti-6Al-2Sn-4Zr-2Mo, Ti-5Al-2Sn-2Zr-4Mo-4Cr, Ti-11.5Mo-6Zr-4.5Sn, Ti-15V-3Cr-3Al-3Sn, Ti-15Mo-5Zr -3Al, Ti-15Mo-5Zr, Ti-13V-11Cr-3Al, or the like can be used.

In the manufacture of antibacterial products for medical doctors of the first invention, at least a surface layer is made of a base material made of titanium or a titanium alloy, a base material such as a surgical instrument, and the surface layer is mainly composed of hydrocarbon, particularly acetylene. The heat treatment is performed at a high temperature by using a combustion flame of the gas to be used, particularly a reducing flame. This hydrocarbon-based gas means a gas containing at least 50% by volume of hydrocarbon, for example, a gas containing at least 50% by volume of acetylene and appropriately mixed with air, hydrogen, oxygen, etc. To do. In the production of the antibacterial product for doctors of the present invention, the gas containing hydrocarbon as a main component preferably contains 50% by volume or more of acetylene, and the hydrocarbon is most preferably 100% of acetylene. When unsaturated hydrocarbons, especially acetylene having a triple bond, are used, in the process of combustion, especially in the reducing flame part, the unsaturated bond part decomposes to form an intermediate radical substance. It is considered that carbon doping is likely to occur because of its high activity.

  In the manufacture of the antibacterial product for medical doctors of the present invention, when the surface layer of the substrate to be heat-treated is titanium or a titanium alloy, oxygen that oxidizes the titanium or titanium alloy is necessary, and air or oxygen is supplied accordingly. Need to contain.

In the manufacture of the antibacterial product for medical doctors of the first invention, the surface of the substrate whose surface layer is made of titanium or a titanium alloy is heated at a high temperature using a combustion flame of a gas mainly composed of hydrocarbon. In this case, even if a combustion flame of a gas containing hydrocarbon as a main component is directly applied to the surface of the substrate and heat-treated at a high temperature, the surface of such a substrate is in a combustion gas atmosphere of a gas containing hydrocarbon as a main component. The heat treatment may be carried out at a high temperature, and this heat treatment can be carried out, for example, in a furnace. When heat treatment is performed at a high temperature by directly applying a combustion flame, the above-described fuel gas may be burned in a furnace and the combustion flame may be applied to the surface of the substrate. When heat treatment is performed in a combustion gas atmosphere at a high temperature, the above fuel gas is burned in a furnace and the high-temperature combustion gas atmosphere is used.

  Regarding the heat treatment in the first invention, the surface temperature of the substrate is 900 to 1500 ° C., preferably 1000 to 1200 ° C., and carbon is doped with carbon in a Ti—C bond state as the surface layer of the substrate. It is necessary to heat-process so that a layer may be formed. In the case of the heat treatment in which the surface temperature of the substrate ends below 900 ° C., the durability of the substrate having the carbon-doped titanium oxide layer obtained is insufficient and the photocatalytic activity under visible light is also insufficient. On the other hand, in the case of heat treatment in which the surface temperature of the substrate exceeds 1500 ° C., the ultrathin film is peeled off from the surface of the substrate during cooling after the heat treatment, and has the visible light response that is the object of the first invention. It is impossible to obtain an antibacterial product for doctors equipped with a carbon-doped titanium oxide layer having high durability (high hardness, scratch resistance, abrasion resistance, chemical resistance, heat resistance).

  Moreover, even in the case of heat treatment in which the surface temperature of the substrate is in the range of 900 to 1500 ° C., if the heat treatment time is long, peeling of the ultrathin film from the surface portion of the substrate occurs during cooling after the heat treatment, Since the effect such as durability which is the object of the first invention cannot be obtained, it is necessary to have a time that does not cause peeling on the surface of the substrate during cooling after the heat treatment. That is, the heat treatment time is sufficient to make the surface layer a carbon-doped titanium oxide layer doped with carbon in a Ti-C bond state. It must be a time that does not result in peeling of the thin film. This heat treatment time is correlated with the heating temperature, but is preferably about 400 seconds or less.

By adjusting the heating temperature and the heat treatment time, a carbon-doped titanium oxide layer in which carbon containing 0.3 to 15 at%, preferably 1 to 10 at%, is doped with a Ti—C bond in a carbon state is relatively easy. Obtainable. When the carbon doping amount is small, the carbon-doped titanium oxide layer is transparent, and as the carbon doping amount increases, the carbon-doped titanium oxide layer becomes translucent and opaque. Therefore, by forming a transparent carbon-doped titanium oxide layer on a transparent plate-shaped core material, it has excellent durability (high hardness, scratch resistance, abrasion resistance, chemical resistance, heat resistance) and visible light response A transparent plate that functions as a mold photocatalyst can be obtained, and durability (high hardness, scratch resistance, abrasion resistance) can be obtained by forming a transparent carbon-doped titanium oxide layer on a plate having a colored pattern on the surface. , A decorative plate that is excellent in chemical resistance and heat resistance) and functions as a visible light responsive photocatalyst. In the case where at least the substrate whose surface layer is made of titanium or a titanium alloy is composed of the surface portion forming layer and the core material, and the thickness of the surface portion forming layer is 500 nm or less, the melting point of the surface portion forming layer When heated to the vicinity, many small island-like undulations floating in the sea are generated on the surface and become translucent.

  In the antibacterial product for doctors having a carbon-doped titanium oxide layer doped with carbon in a Ti—C bond state, the thickness of the carbon-doped titanium oxide layer is preferably 10 nm or more, and has high hardness and scratch resistance. In order to achieve wear resistance, the thickness is more preferably 50 nm or more. When the thickness of the carbon-doped titanium oxide layer is less than 10 nm, the durability of the antibacterial product for doctors having the obtained carbon-doped titanium oxide layer tends to be insufficient. The upper limit of the thickness of the carbon-doped titanium oxide layer is not particularly limited, although it is necessary to consider the cost and the effect achieved.

The carbon-doped titanium oxide layer of the antibacterial product for medical doctors of the first invention is doped with chemically modified titanium oxide as described in Non-Patent Document 3 described above, and various conventionally proposed atoms or anions X Unlike titanium oxide containing the titanium compound Ti—O—X, the carbon is contained in a relatively large amount, and doped carbon is contained in a Ti—C bond state. As a result, it is considered that mechanical strength such as scratch resistance and abrasion resistance is improved, and the Vickers hardness is remarkably increased. Moreover, heat resistance is also improved.

  The carbon-doped titanium oxide layer of the antibacterial product for doctors of the first invention has a Vickers hardness of 300 or more, preferably 500 or more, more preferably 700 or more, and most preferably 1000 or more. A Vickers hardness of 1000 or more is harder than that of hard chrome plating. Therefore, the first multifunctional material can be significantly used for various antibacterial products for doctors for which hard chrome plating has been conventionally used.

  Such a carbon-doped titanium oxide layer responds not only to ultraviolet rays but also to visible light having a wavelength of 400 nm or more, and functions effectively as a photocatalyst. Therefore, the antibacterial product for medical doctors of the first invention exhibits functions such as high bactericidal properties, antibacterial properties and deodorization even with visible light by the action of the visible light responsive photocatalyst. The carbon-doped titanium oxide layer exhibits super hydrophilicity with a contact angle of 3 ° or less. Therefore, it is easy to clean and the water drains quickly.

Furthermore, the carbon-doped titanium oxide layer of the antibacterial product for medical doctors of the first invention is also excellent in chemical resistance, and after being immersed in an aqueous solution of 1M sulfuric acid and 1M sodium hydroxide for one week, the film hardness and abrasion resistance When the property and the photocurrent density were measured and compared with the measured values before the treatment, no significant change was observed. Therefore, by using carbon-doped titanium oxide as the surface layer of various instruments that are cleaned and disinfected by chemicals, it is possible to provide a highly durable antibacterial product for doctors that is unlikely to cause corrosion.
Incidentally, with respect to commercially available titanium oxide films, generally, the binder dissolves in acid or alkali depending on the kind thereof, so that the film peels off, and there is almost no acid resistance and alkali resistance.

The antibacterial product for doctors of the second invention is obtained by heat-treating the surface layer of the substrate having at least a surface layer made of titanium or a titanium alloy as in the antibacterial product for doctors of the first invention, and at least the surface layer is titanium. Alternatively, the surface of the substrate made of titanium alloy is heat-treated with, for example, a combustion flame of unsaturated hydrocarbon, particularly acetylene, to form a layer in which fine columns made of titanium oxide or titanium alloy oxide stand in the surface layer And then applying, for example, thermal stress, shear stress, tensile force, and cutting the layer in which the microcolumns are erected in a direction along the surface layer to at least a portion of the substrate, usually the A member in which a layer of fine columns made of titanium oxide or titanium alloy oxide is exposed on the majority of the substrate, and a plurality of continuous narrow widths made of titanium oxide or titanium alloy oxide on the thin film Protrusion And fine Column protruding have bristled on raised portions can be produced by obtaining the member exposed.

Substrate at least the surface layer is made of titanium or titanium alloy, the whole may be constituted by either a titanium or titanium alloy, or the surface portion forming layer and other material made of titanium or a titanium alloy of the base body It may be composed of a core material. Further, the shape of the substrate may be any final product shape (flat plate shape or three-dimensional shape) where photocatalytic activity and / or super hydrophilicity is desired.

In the case where at least the substrate whose surface layer is made of titanium or a titanium alloy is composed of a surface portion forming layer made of titanium or a titanium alloy and a core material made of another material, the thickness (amount) of the surface portion forming layer ) Even if the thickness is comparable to the amount of layers in which fine columns made of titanium oxide or titanium alloy oxide are formed (that is, the entire surface layer forming layer is made of titanium oxide or titanium alloy oxide). The fine pillars become forested layers) and may be thicker (that is, the fine pillars in which part of the surface portion forming layer in the thickness direction is made of titanium oxide or titanium alloy oxide are forested. Layer, and the rest remains unchanged). The material of the core material is not particularly limited as long as it does not burn, melt or deform during the heat treatment in the manufacture of the antibacterial product for doctors of the second invention. For example, iron, iron alloy, non-ferrous alloy, glass, ceramics, and other ceramics can be used as the core material. As the substrate composed of such a thin film-like surface layer and a core material, those similar to those described in the first invention can be used. The thickness of this surface layer is preferably 0.5 μm or more, more preferably 4 μm or more.

  As the titanium alloy, various known titanium alloys can be used, and the titanium alloy is not particularly limited, and those similar to the first invention are used.

In the production of the second antibacterial product for doctors, for example, it is desirable to use a combustion flame of a gas mainly composed of unsaturated hydrocarbons, particularly acetylene, and particularly to use a reducing flame. In the production of the second antibacterial product for physicians, a gas containing at least 50% by volume of unsaturated hydrocarbon, for example, a gas containing at least 50% by volume of acetylene and appropriately mixed with air, hydrogen, oxygen, or the like is used. Is preferred. In the production of the second medical antibacterial product, it is most preferable that the fuel component is 100% acetylene. When unsaturated hydrocarbons, especially acetylene having a triple bond, are used, in the process of combustion, especially in the reducing flame part, the unsaturated bond part decomposes to form an intermediate radical substance. Has a strong activity, and carbon doping is likely to occur, and doped carbon is contained in a Ti-C bond state.
Thus, when carbon dope is generated in the fine pillars, the hardness of the fine pillars is increased, and as a result, the mechanical strength such as the surface layer hardness and wear resistance of the antibacterial product for doctors is improved, and the heat resistance is also improved. Of course, VOC can also be easily adsorbed by increasing the surface area, and the activity as a photocatalyst is increased. Further, due to carbon doping, this fine column also functions as a visible light responsive photocatalyst.

In the production of the second antibacterial product for doctors, the surface layer is heated by directly applying a combustion flame to the surface of the substrate made of titanium or a titanium alloy, or the surface of the substrate is heated in a combustion exhaust gas atmosphere. However, this heat treatment can be carried out, for example, with a gas burner or in a furnace. When the combustion flame is directly applied and heat treatment is performed at a high temperature, the combustion flame may be applied to the surface of the substrate by a gas burner. When heat treatment is performed in a combustion exhaust gas atmosphere at a high temperature, the above-described fuel gas may be burned in a furnace and an atmosphere containing the high-temperature combustion exhaust gas may be used.

For the heat treatment, at least the surface layer is made of titanium or a titanium alloy, a layer in which fine columns made of titanium oxide or a titanium alloy oxide are formed is formed inside the surface layer, and then, for example, thermal stress, shear stress, By applying a tensile force, the layer in which the fine columns are erected is cut in a direction along the surface layer, and at least a part of the titanium oxide or titanium alloy oxide is erected in at least a part of the substrate. A member in which a layer is exposed, and a member in which a large number of continuous narrow protrusions made of titanium oxide or titanium alloy oxide on a thin film and fine columns standing on the protrusions are exposed Therefore, it is necessary to adjust the heating temperature and the heat treatment time. This heat treatment is preferably performed at a temperature of 600 ° C. or higher.

By performing the heat treatment under such conditions, the height of the layer in which the fine pillars stand is about 1 to 20 μm, and the thickness of the thin film thereon is about 0.1 to 10 μm. Intermediates having an average thickness of about 0.2 to 3 μm are formed. Thereafter, for example, by applying a thermal stress, a shear stress, or a tensile force to cut the layer in which the fine pillars are erected in a direction along the surface layer, at least a part of the titanium oxide or the substrate is formed on the substrate. A member in which a layer with fine columns made of titanium alloy oxide is exposed (that is, all or most of the thin film existing on the layer with fine columns on the substrate is peeled off) However, a part of the thin film existing on the layer where the fine pillars are erected may remain without being peeled) and a large number of continuous narrow widths made of titanium oxide or titanium alloy oxide on the thin film A protrusion and a member in which a fine pillar standing on the protrusion is exposed are obtained.

  In the case of cutting a layer in which fine columns are erected by applying thermal stress in a direction along the surface layer, for example, either the surface or the back surface of the substrate is cooled or heated to heat the surface of the substrate. A temperature difference is provided between the back surface and the back surface. As this cooling method, for example, either the surface or the back surface of the hot intermediate is brought into contact with a cooling object, such as a stainless steel block, or cold air (room temperature air) is applied to either the surface or the back surface of the hot intermediate. Spray. Even if the hot intermediate is allowed to cool, thermal stress is generated, but the degree is low.

  When shearing stress is applied and the layer in which the fine pillars are erected is cut in a direction along the surface layer, for example, a relatively reverse force is applied to the front and back surfaces of the intermediate by frictional force. In addition, when a layer in which fine columns are erected is cut in a direction along the surface layer by applying a tensile force, for example, the surface and the back surface of the above intermediate body are removed from those surfaces using a vacuum suction disk or the like. Pull in the opposite direction in the vertical direction. When using only a member in which a layer in which fine columns made of titanium oxide or titanium alloy oxide are forested is exposed on at least a part of the substrate, oxidation is performed on the intermediate thin film. A portion corresponding to a member in which a large number of continuous narrow protrusions made of titanium or a titanium alloy oxide and fine columns standing on the protrusions are exposed can be removed by polishing, sputtering, or the like.

In the antibacterial product for doctors where a layer in which fine columns made of titanium oxide or titanium alloy oxide are forested is exposed on at least a part of the substrate obtained as described above, the fine columns are forested. The height of the layer where the fine column stands is changed depending on the height position of the fine column obtained by cutting the layer along the surface layer, but the height of the layer where the fine column stands is generally Is about 1 to 20 μm, and the average thickness of the fine columns is about 0.5 to 3 μm. This member can easily adsorb VOC, has a large surface area, has high activity as a photocatalyst, and also has high film hardness, antibacterial products for doctors with excellent peeling resistance, abrasion resistance, chemical resistance, and heat resistance. It is.

On the other hand, on the thin film obtained as described above, a large number of continuous narrow protrusions made of titanium oxide or titanium alloy oxide and members with exposed fine columns standing on the protrusions are small. The height of the protrusion on each small piece is about 2 to 12 μm, and the height of the fine column is the height of the fine column obtained by cutting the layer in which the fine column stands in the direction along the surface layer. Although the height varies depending on the position, the height of the layer in which the fine pillars stand is generally about 1 to 5 μm, and the average thickness of the fine pillars is about 0.2 to 0.5 μm. However, depending on the conditions for cutting the layer in which the fine columns are erected in the direction along the surface layer, there are cases where a large number of continuous narrow protrusions are exposed without the presence of the fine columns. This member can also adsorb VOCs and has a large surface area, so it has high activity as a photocatalyst. Further, this member can be used as it is or after being pulverized, and the pulverized product can easily adsorb VOC and has a large surface area, so it has high activity as a photocatalyst.
In the second antibacterial product for doctors, carbon-doped fine columns made of titanium oxide or titanium alloy oxide, a large number of continuous narrow projections and fine columns standing on the projections are carbon-doped. It responds not only to ultraviolet rays but also visible light having a wavelength of 400 nm or more, acts particularly effectively as a photocatalyst, and can be used as a visible light responsive photocatalyst, and exhibits a photocatalytic function not only outdoors but also indoors.

  The shape of each of the fine columns of the layer in which the fine columns made of titanium oxide or titanium alloy oxide constituting the second antibacterial product for doctors stands is judged from the micrographs of FIGS. 10 and 13. In addition, a prismatic shape, a cylindrical shape, a pyramid shape, a conical shape, an inverted pyramid shape or an inverted conical shape, etc., which extends straight or perpendicular to the surface of the substrate, extends while being curved or bent. , Branched and extended, and composites thereof. Moreover, as the whole shape, it can show by various expressions, such as a frost column shape, a raising carpet shape, a basket shape, a row column shape, and the column shape assembled with blocks. In addition, the thickness and height of the fine columns, the size of the base (bottom surface), and the like vary depending on heating conditions and the like.

  A member in which a large number of continuous narrow protrusions made of titanium oxide or a titanium alloy oxide in a thin film form and fine columns standing on the protrusions are exposed is judged from the micrograph in FIG. In addition, it can be seen that the many continuous narrow protrusions look like the outside of the walnut shell and the appearance of pumice. It can be seen that the pattern is bent. In addition, the shape of the fine column standing on the protrusion is the same as the shape of each fine column in the layer where the fine column on the base is standing, but the junction between the fine column and the thin film Therefore, the density of the fine columns standing on the protrusion is generally smaller than the density of the fine columns in the layer where the fine columns on the base are standing.

  Below, based on an Example and a comparative example, the carbon dope titanium oxide layer formed in the surface of the antibacterial product for doctors of this invention is demonstrated in detail.

[Examples 1 to 3]
Using an acetylene flame, a titanium plate with a thickness of 0.3 mm has a surface temperature of about 1100 ° C.
Then, a titanium plate having a carbon-doped titanium oxide layer doped with carbon in a Ti—C bond state was formed as a surface layer. By adjusting the heat treatment time at 1100 ° C. to 5 seconds (Example 1), 3 seconds (Example 2), and 1 second (Example 3), respectively, the amount of carbon doping and the thickness of the carbon-doped titanium oxide layer were reduced. Titanium plates with different carbon doped titanium oxide layers were formed.

The carbon content was calculated | required with the fluorescent-X-ray-analysis apparatus about the carbon dope titanium oxide layer with which the carbon formed in this Example 1-3 was doped in the state of Ti-C bond. Assuming a molecular structure of TiO _2-x C x based on the carbon content, carbon content 8at% for Example 1, TiO _{1. 76} C _0.24, carbon content of about 3.3At% for Examples 2, TiO _1.90 C _0.10 and Example 3 had a carbon content of 1.7 at% and TiO _1.95 C _0.05 . Examples 1 to
The carbon-doped titanium oxide layer in which the carbon formed in 3 was doped in a Ti—C bond state was superhydrophilic with a contact angle with a water droplet of about 2 °.

[Comparative Example 1]
A commercially available titanium oxide sol (STS-01 manufactured by Ishihara Sangyo Co., Ltd.) was spin-coated on a titanium plate having a thickness of 0.3 mm, and then a titanium plate having a titanium oxide film whose adhesion was improved by heating was formed.

[Comparative Example 2]
A commercially available product in which titanium oxide was spray-coated on a SUS plate was used as the substrate having the titanium oxide film of Comparative Example 2.

Test Example 1 (Vickers hardness)
The carbon-doped titanium oxide layer doped with the carbon of Example 1 in a Ti—C bond state and the titanium oxide film of Comparative Example 1 were subjected to indenter: Belkovic using a nanohard nesting tester (NHT) (manufactured by CSM Instruments, Switzerland). When the film hardness was measured under the conditions of type, test load: 2 mN, load unloading speed: 4 mN / min, the carbon-doped titanium oxide layer doped with carbon in the state of Ti-C bond in Example 1 had a Vickers hardness. Was a high value of 1340. On the other hand, the Vickers hardness of the titanium oxide film of Comparative Example 1 was 160.

These results are shown in FIG. For reference, the literature values of Vickers hardness of hard chrome plating layer and nickel plating layer (Tomono, “Practical Plating Manual”, Chapter 6, Ohmsha (1971)) are also shown. It is obvious that the carbon-doped titanium oxide layer in which the carbon of Example 1 is doped in a Ti—C bond state has higher hardness than the nickel plating layer and the hard chromium plating layer.

Test Example 2 (Scratch resistance)
For the carbon-doped titanium oxide layer doped with the carbon of Example 1 in a Ti—C bond state and the titanium oxide film of Comparative Example 1, a microscratch tester (MST) (manufactured by CSM Instruments, Switzerland) was used as an indenter: Rockwell. The scratch resistance test was performed under the conditions of (diamond), tip radius 200 μm, initial load: 0 N, final load: 30 N, load speed: 50 N / min, scratch length: 6 mm, stage speed: 10.5 mm / min. A “peeling start” load at which a small film peels off within the scratch mark and an “overall peel” load at which the film peels across the scratch mark were determined. The results were as shown in Table 1.

  As is apparent from this table, it can be seen that the carbon-doped titanium oxide surface layer of Example A is superior to the titanium oxide film of Comparative Example 1 in scratch resistance.

Test Example 3 (Abrasion resistance)
The carbon-doped titanium oxide layer doped with the carbon of Example 1 in a Ti—C bond state and the titanium oxide film of Comparative Example 1 were tested at a test temperature using a high-temperature tribometer (HT-TRM) (manufactured by CSM Instruments, Switzerland). A wear test was performed under the conditions of: room temperature and 470 ° C., ball: SiC sphere having a diameter of 12.4 mm, load: 1 N, sliding speed: 20 mm / sec, rotation radius: 1 mm, test rotation speed: 1000 rotations.

  As a result, for the titanium oxide film of Comparative Example 1, peeling occurred at both room temperature and 470 ° C., but for the carbon-doped titanium oxide layer in which the carbon of Example 1 was doped in a Ti—C bond state, No significant trace wear was detected under both room temperature and 470 ° C conditions.

Test Example 4 (Chemical resistance)
After immersing the titanium plate having the carbon-doped titanium oxide layer doped with the carbon of Example 1 in a Ti—C bond state in a 1M sulfuric acid aqueous solution and a 1M sodium hydroxide aqueous solution for 1 week at room temperature, When the wear resistance and the photocurrent density described below were measured, no significant difference was observed in the results before and after immersion. That is, it was confirmed that the carbon-doped titanium oxide layer in which the carbon of Example 1 was doped in a Ti—C bond state had high chemical resistance.

Test Example 5 (Structure of carbon-doped titanium oxide layer doped with carbon in a Ti-C bond state)
For the carbon-doped titanium oxide layer in which the carbon of Example 1 was doped in a Ti—C bond state, the acceleration voltage was 10 kV, the target was Al, and Ar ion sputtering was performed for 2700 seconds using an X-ray photoelectron spectrometer (XPS). Done and started the analysis. If this sputtering rate is 0.64 Å / s corresponding to the SiO ₂ film, the depth is about 173 nm. The result of the XPS analysis is shown in FIG. The highest peak appears when the binding energy is 284.6 eV. This is judged to be a C—H (C) bond commonly found in Cls analysis. The next highest peak is seen when the binding energy is 281.7 eV. Since the bond energy of the Ti—C bond is 281.6 eV, it is determined that C is doped as a Ti—C bond in the carbon-doped titanium oxide layer of Example 1. As a result of XPS analysis at 11 points at different positions in the depth direction of the carbon-doped titanium oxide layer, similar peaks appeared in the vicinity of 281.6 eV at all points.

  Ti-C bonds were also confirmed at the boundary between the carbon-doped titanium oxide layer and the substrate. Accordingly, the hardness is increased due to the Ti—C bond in the carbon-doped titanium oxide layer, and the film peeling strength is significantly increased due to the Ti—C bond at the boundary between the carbon-doped titanium oxide layer and the substrate. Is expected.

Test Example 6 (wavelength response)
The wavelength responsiveness of the carbon-doped titanium oxide layer in which the carbons of Examples 1 to 3 were doped in a Ti—C bond state and the titanium oxide films of Comparative Examples 1 and 2 were measured using an Oriel monochromator. Specifically, a voltage of 0.3 V was applied to each layer and film between the counter electrode in a 0.05 M aqueous sodium sulfate solution, and the photocurrent density was measured.

The result is shown in FIG. FIG. 3 shows the obtained photocurrent density jp with respect to the irradiation wavelength. The wavelength absorption edge of the carbon-doped titanium oxide layer in which the carbons of Examples 1 to 3 are doped in a Ti—C bond state extends to 490 nm, and the photocurrent density increases as the carbon doping amount increases. Was recognized. Although not shown here, it has been found that when the carbon doping amount exceeds 10 at%, the current density tends to decrease, and when the carbon doping amount exceeds 15 at%, the tendency becomes remarkable. Therefore, it was recognized that the carbon doping amount has an optimum value of about 1 to 10 at%. On the other hand, in the titanium oxide films of Comparative Examples 1 and 2, it was confirmed that the photocurrent density was extremely small and the wavelength absorption edge was about 410 nm.

Test example 7 (light energy conversion efficiency)
For the carbon-doped titanium oxide layer in which the carbons of Examples 1 to 3 are doped in a Ti—C bond state and the titanium oxide films of Comparative Examples 1 and 2, the formula η = jp (Ews−Eapp) / I
The light energy conversion efficiency η defined by Here, Ews is the theoretical decomposition voltage of water (= 1.23 V), Eapp is the applied voltage (= 0.3 V), and I is the irradiation light intensity. The result is shown in FIG. FIG. 4 shows the light energy conversion efficiency η with respect to the irradiation light wavelength.

  As is clear from FIG. 4, the carbon-doped titanium oxide layer in which the carbons of Examples 1 to 3 are doped in a Ti—C bond state has extremely high light energy conversion efficiency, and the conversion efficiency in the vicinity of a wavelength of 450 nm is a comparative example. It was recognized that the conversion efficiency in the ultraviolet region (200 to 380 nm) of the 1 and 2 titanium oxide films was superior. Further, the water decomposition efficiency of the carbon-doped titanium oxide layer in which the carbon of Example 1 is doped in a Ti—C bond state is about 8% at a wavelength of 370 nm, and an efficiency exceeding 10% can be obtained at 350 nm or less. I understood.

Test Example 8 (Deodorization test)
A deodorizing test was performed on the carbon-doped titanium oxide layer in which the carbons of Examples 1 and 2 were doped in a Ti-C bond state and the titanium oxide film of Comparative Example 1. Specifically, after acetaldehyde generally used in deodorization tests is enclosed in a 1000 ml glass container together with a substrate having a carbon-doped titanium oxide layer, the influence of concentration reduction due to initial adsorption can be ignored. Visible light was irradiated with a fluorescent lamp with a UV cut filter, and the acetaldehyde concentration was measured by gas chromatography at every predetermined irradiation time. The surface area of each film is 8.0c.
It was m ^2.

  The result is shown in FIG. FIG. 5 shows the acetaldehyde concentration with respect to the elapsed time after irradiation with visible light. The acetaldehyde decomposition rate of the carbon-doped titanium oxide layers of Examples 1 and 2 is higher than the acetaldehyde decomposition rate of the titanium oxide film of Comparative Example 1, and the carbon doping amount is large. It was found that the carbon-doped titanium oxide layer of Example 1 having a higher energy conversion efficiency has a higher decomposition rate than the carbon-doped titanium oxide layer of Example 2.

Test example 9 (antifouling test)
An antifouling test was carried out on the carbon-doped titanium oxide layer of Example 1 and the titanium oxide film of Comparative Example 1. Each coating was placed in a smoking room in the Central Research Institute of Electric Power Co., Ltd., and surface contamination after 145 days was observed. There is no direct incidence of sunlight in the smoking room.

  A photograph showing the results is shown in FIG. Fat was attached to the surface of the titanium oxide film of Comparative Example 1 and had a pale yellow color, but the surface of the carbon-doped titanium oxide layer of Example 1 was not particularly changed and was kept clean. It was confirmed that the antifouling effect was sufficiently exhibited.

[Examples 4 to 7]
Using a acetylene combustion flame in the same manner as in Examples 1 to 3, a 0.3 mm thick titanium plate was
The titanium plate which has a carbon dope titanium oxide layer as a surface layer was formed by heat-processing for the time shown in Table 2 at the surface temperature shown in a table | surface.

[Comparative Example 3]
Using a natural gas combustion flame, a titanium plate with a thickness of 0.3 mm is
Heat treatment was performed for the time shown in the table.

Test Example 10
The Vickers hardness (HV) of the carbon-doped titanium oxide layers of Examples 4 to 7 and the film of Comparative Example 3 was measured in the same manner as in Test Example 1 above. The results are shown in Table 2. Moreover, the carbon dope titanium oxide layer formed in Examples 4-11 was super hydrophilicity whose contact angle with a water droplet was about 2 degrees.

  As is apparent from the data shown in Table 2, when the heat treatment was performed with the combustion gas of natural gas so that the surface temperature became 850 ° C., only a film having a Vickers hardness of 160 was obtained, but the surface temperature was 1000 ° C. In Examples 4 to 7 where heat treatment was performed using acetylene combustion gas as described above, a carbon-doped titanium oxide layer having a Vickers hardness of 1200 was obtained.

Test Example 11
For the carbon-doped titanium oxide layers of Examples 4 to 7 and the titanium oxide films of Comparative Examples 1 and 3, as in Test Example 6, a voltage of 0.3 V was applied between the counter electrode in a 0.05 M sodium sulfate aqueous solution. The photocurrent density was measured by irradiating with light of 300 nm to 520 nm. The result is shown in FIG. FIG. 7 shows the obtained photocurrent density jp with respect to the potential ECP (V vs. SSE).

  The carbon-doped titanium oxide layers of Examples 4 to 6 obtained by heat treatment using an acetylene combustion gas so that the surface temperature becomes 1000 to 1200 ° C. have relatively high photocurrent density and are excellent. all right. On the other hand, the titanium oxide of Comparative Example 3 obtained by heat treatment so that the surface temperature becomes 850 ° C. and the carbon-doped titanium oxide layer of Example 7 obtained by heat treatment so that the surface temperature becomes 1500 ° C. It was found that the current density was relatively small.

[Example 8]
A titanium alloy whose surface layer contains carbon-doped titanium oxide by heat treatment of a Ti-6Al-4V alloy plate having a thickness of 0.3 mm using an acetylene combustion flame so that its surface temperature is about 1100 ° C. An alloy plate made of The heat treatment time at 1100 ° C. was 60 seconds. The layer containing carbon-doped titanium oxide thus formed is superhydrophilic with a contact angle with water droplets of about 2 °, and has the same photocatalytic activity as that of the carbon-doped titanium oxide layer obtained in Example 4. showed that.

[Example 9]
A titanium thin film having a thickness of about 500 nm was formed on the surface of a stainless steel plate (SUS316) having a thickness of 0.3 mm by sputtering. A stainless steel sheet having a carbon-doped titanium oxide layer as a surface layer was formed by heat treatment using an acetylene combustion flame so that the surface temperature was about 900 ° C. The heat treatment time at 900 ° C. was 15 seconds. The carbon-doped titanium oxide layer thus formed is superhydrophilic with a contact angle with water droplets of about 2 °, and exhibits the same photocatalytic activity as the carbon-doped titanium oxide layer obtained in Example 4. It was.

[Example 10]
A titanium oxide powder having a particle size of 20 μm is supplied into an acetylene combustion flame, and is retained in the combustion flame for a predetermined time, and heat-treated so that the surface temperature is about 1000 ° C. A titanium powder having a layer was formed. The heat treatment time at 1000 ° C. was 4 seconds. The titanium powder having the carbon-doped titanium oxide layer formed as described above showed the same photocatalytic activity as that of the carbon-doped titanium oxide layer obtained in Example 4.

[Examples 11 to 12]
A titanium thin film having a thickness of about 100 nm was formed by sputtering on the surface of a 1 mm thick glass plate (Pyrex (registered trademark)). A glass plate having a carbon-doped titanium oxide layer as a surface layer is obtained by heat treatment using an acetylene combustion flame so that the surface temperature is 1100 ° C. (Example 11) or 1500 ° C. (Example 12). Formed. The heat treatment time at 1100 ° C. or 1500 ° C. was 10 seconds. The carbon-doped titanium oxide layer thus formed was transparent as shown in the photograph in FIG. 8A when the surface temperature was 1100 ° C., but when the surface temperature was 1500 ° C., FIG. As shown in FIG. 8, many small island-like undulations floating in the sea are generated on the surface, and it became translucent as shown in FIG.

[Examples 13 to 16]
The surface of the titanium plate having a thickness of 0.3 mm was subjected to heat treatment with an acetylene combustion flame at the surface layer temperature shown in Table 3 for the time shown in Table 3. After that, when the surface to which the flame is applied is brought into contact with a flat surface of a stainless steel block having a thickness of 30 mm and cooled, a layer in which fine columns made of white titanium oxide stand on the most part of the titanium plate surface is exposed. And a small piece member in which a large number of continuous narrow protrusions made of white titanium oxide on the thin film and fine columns standing on the protrusions are exposed. That is, the layer in which the fine columns made of titanium oxide formed in the surface layer by heat treatment are erected is cut in the direction along the surface layer by the subsequent cooling. In this way, Examples 13 to 16 were obtained.

  FIG. 10 is a photomicrograph of the member obtained in Example 13, in which a layer 2 in which fine columns made of white titanium oxide are forested is exposed on the titanium plate surface 1, and a white color is formed on the thin film. A state is shown in which a small piece member 3 in which a large number of continuous narrow protrusions made of titanium oxide and fine columns standing on the protrusions are exposed remains on a part of the layer 2. In addition, in the manufacturing method of Examples 13-16, although the titanium plate surface 1 is not exposed, the micrograph of FIG. 10 has shown the state which removed a part of layer 2 in which the fine pillar stands. FIG. 11 is a photomicrograph showing the state of the surface on the thin film side of the small piece member 3 in which a large number of continuous narrow protrusions made of white titanium oxide and thin columns standing on the protrusions are exposed on the thin film. FIG. 12 shows a number of continuous narrow widths of small piece members 3 in which a large number of continuous narrow-width projections made of white titanium oxide are exposed on a thin film and fine columns standing on the projections are exposed. FIG. 13 is a photomicrograph showing the state of the protrusion and the surface on the side where the fine pillar standing on the protrusion is exposed, and FIG. 13 is the state of the layer 2 where the fine pillar made of white titanium oxide is standing FIG.

[Example 17]
The surface of a Ti-6Al-4V alloy plate having a thickness of 0.3 mm was heat-treated with an acetylene combustion flame at the surface layer temperature shown in Table 3 for the time shown in Table 3. After that, when the surface to which the flame is applied is brought into contact with a flat surface of a stainless steel block having a thickness of 30 mm and cooled, a layer in which fine columns made of titanium alloy oxide stand on most of the surface of the titanium alloy plate is exposed. And a small piece member in which a number of continuous narrow protrusions made of titanium alloy oxide on the thin film and fine columns standing on the protrusions are exposed.

[Example 18]
A titanium thin film having a thickness of about 3 μm was formed on the surface of a stainless steel plate (SUS316) having a thickness of 0.3 mm by electron beam evaporation. The surface of the thin film was heat-treated with an acetylene combustion flame at the surface layer temperature shown in Table 3 for the time shown in Table 3. After that, when the surface to which the combustion flame is applied is brought into contact with a flat surface of a 30 mm thick stainless steel block and cooled, a layer in which fine columns made of white titanium oxide are forested is exposed on the majority of the surface of the stainless steel plate. And a small piece member in which a large number of continuous narrow protrusions made of white titanium oxide on the thin film and fine columns standing on the protrusions are exposed.

[Comparative Example 4]
A commercially available titanium oxide sol (STS-01 manufactured by Ishihara Sangyo Co., Ltd.) was spin-coated on a titanium plate having a thickness of 0.3 mm, and then a titanium plate having a titanium oxide film whose adhesion was improved by heating was formed.

Test Example 12 (Scratch hardness test: pencil method)
Mitsubishi Pencil Co., Ltd., based on JIS K 5600-5-4 (1999), on the surface of the fine column side of the member in which the layer in which the fine column is grown is exposed on the substrate surface obtained in Examples 13 to 18 A pencil scratch hardness test was carried out using Uni 1H-9H pencils. The results were as shown in Table 3. That is, no damage was observed when a 9H pencil was used for all the test pieces.

Test Example 13 (Chemical resistance test)
The members having exposed layers with fine pillars exposed on the substrate surfaces obtained in Examples 13 to 18 were immersed in 1M sulfuric acid aqueous solution and 1M sodium hydroxide aqueous solution for 1 week at room temperature, washed with water and dried. Then, the above scratch hardness test: the pencil method was carried out. The results were as shown in Table 3. That is, even when a 9H pencil was used for all the test pieces, no damage was observed, and it was confirmed that the test pieces had high chemical resistance.

Test example 14 (heat resistance test)
A member in which a layer in which fine columns are erected is exposed on the surface of the substrate obtained in Examples 13 to 18 is placed in a tubular furnace, and the temperature is raised from room temperature to 500 ° C. in an air atmosphere over 1 hour. After holding at a constant temperature of 500 ° C. for 2 hours and further allowing to cool to room temperature over 1 hour, the above-described scratch hardness test: pencil method was performed. The results were as shown in Table 3. That is, no damage was observed even when a 9H pencil was used for all the test pieces, and it was confirmed that the specimen had high heat resistance.

Test Example 15 (Anti-fouling test)
As a sample, a titanium plate surface area 8 cm ² having a titanium oxide film obtained in member and Comparative Example 4 of surface area 8 cm ² of the layer minute columns the resulting substrate surface in Example 16 is bristled is exposed An antifouling test was conducted using Specifically, each of these samples was immersed in 80 mL of an aqueous methylene blue solution adjusted to a concentration of about 10 μmol / L, and the influence of the decrease in concentration due to initial adsorption became negligible. Matsushita Electric Industrial Co., Ltd. Visible light was irradiated with a fluorescent lamp with a UV cut filter manufactured, and the absorbance of the aqueous methylene blue solution at a wavelength of 660 nm was measured with a water quality inspection apparatus DR / 2400 manufactured by HACH at every predetermined irradiation time. The result was as shown in FIG.

  From FIG. 14, the member in which the layer with the fine pillars exposed on the surface of the substrate obtained in Example 16 is exposed to methylene blue as compared with the titanium plate having the titanium oxide film obtained in Comparative Example 4. It can be seen that the decomposition speed of is high and the antifouling effect is high.

Test Example 16 (Crystal structure and bonding state)
As a result of performing X-ray analysis (XRD) on the sample obtained from the fine column of the member in which the layer with the fine column grown on the substrate surface obtained in Example 15 is exposed, it has a rutile crystal structure. It has been found.

Further, with respect to the fine column portion of the member in which the layer with the fine columns grown on the surface of the substrate obtained in Example 15 is exposed, an X-ray photoelectron spectrometer (XPS) is used to accelerate voltage: 10 kV, target: Al was used for Ar sputtering for 2700 seconds, and analysis was started. If this sputtering rate is 0.64 Å / s corresponding to the SiO ₂ film, the depth is about 173 nm. The result of the XPS analysis was as shown in FIG. The highest peak appears when the binding energy is 284.6 eV. This is judged to be a C—H (C) bond commonly found in Cls analysis. The next highest peak is seen when the binding energy is 281.6 eV. Since the bond energy of the Ti—C bond is 281.6 eV, it is determined that C is doped as a Ti—C bond in the fine column of Example 15. As a result of XPS analysis at 14 points at different heights of the fine columns, similar peaks appeared in the vicinity of 281.6 eV at all points.

[Example 19]
A disk having a diameter of 32 mm and a thickness of 0.3 mm was used as a test piece, and the surface temperature was about 1 on the surface.
The mixture was heated by an acetylene combustion flame so as to be maintained at 150 ° C. About the 1st test piece, the heating was stopped at the time of the heating time of 120 seconds, and it stood to cool. About the 2nd test piece, the heating was stopped at the time of 180 second and it stood to cool. The third test piece was heated for 480 seconds, and immediately the surface to which the flame was applied was brought into contact with the flat surface of a 30 mm thick stainless steel block and cooled. By this cooling, a thin film was peeled off from the surface of the titanium plate, and a member in which a layer in which fine columns made of white titanium oxide were erected was exposed. With respect to these three test pieces, using a FIB-SEM apparatus SMI8400SE manufactured by Seiko Instruments Inc., a hole of 3 μm × 12 μm and a depth of 10 μm was dug on the surface of the test piece, and the side and bottom surfaces thereof were observed with a SEM apparatus VE7800 manufactured by Keyence Corporation. Went. The SEM photograph of the test piece after 120 seconds is FIG. 16, the SEM photograph of the test piece after 180 seconds is FIG. 17, and the SEM photograph of the test piece after 480 seconds is FIG. In FIG. 17 after 180 seconds, signs of a fine column structure begin to appear in the lower part of the film, and it is considered that by continuing the flame treatment, the fine column is elongated and a fine column structure as intended in the present invention is formed. .

[Concrete example]
As a method for handling antibacterial products for medical doctors equipped with the carbon-doped titanium oxide surface layer of the first invention and the second invention, after washing the used product, the water is cut off and a sterilization box that can be irradiated with ultraviolet rays is used. By storing this and irradiating it with ultraviolet rays, it is easier to remove dirt due to the superhydrophilicity of the photocatalyst, and the antibacterial product for doctors is more than ever thanks to the synergistic effect of sterilization by the organic decomposition function of the photocatalyst and sterilization by ultraviolet ray It can be disinfected effectively. In order to improve the superhydrophilicity of the photocatalyst, it is preferable to perform washing while irradiating the product with ultraviolet rays or visible light.

  It is also possible to sterilize and disinfect the photocatalyst by decomposing organic matter by immersing an antibacterial product for medical use with a carbon-doped titanium oxide surface layer after washing in a disinfectant solution and irradiating it with ultraviolet or visible light. Effective disinfection can be performed by the synergistic effect of sterilization by the agent.

  In order to perform such disinfection, a dedicated device equipped with an irradiation device that can irradiate the desired part (usually the whole) of the antibacterial product for doctors with a carbon-doped titanium oxide surface layer immersed in a disinfectant solution. It is also preferable to manufacture a storage tank. As such an apparatus, there is a storage tank whose inner surface is mirror-finished. Preferably, an apparatus for irregularly reflecting light from an irradiation device by forming a large number of irregularities on the inner surface can be considered.

  In addition, since the carbon-doped titanium oxide surface layer of the present invention has a wide photoresponsive area, it exhibits sufficient functions such as sterilization and antibacterial and super hydrophilicity even when irradiated with light in a solution.

It is a figure which shows the result of the film hardness test of Test Example 1. 10 is a diagram showing the results of XPS analysis in Test Example 5. FIG. It is a figure which shows the wavelength response of the photocurrent density of Test Example 6. It is a figure which shows the test result of the light energy conversion efficiency of Test Example 7. It is a figure which shows the result of the deodorizing test of Test Example 8. 10 is a photograph showing the results of an antifouling test in Test Example 9. It is a figure which shows the result of Test Example 11. It is a photograph which shows the light transmission state of the carbon dope titanium oxide layer obtained in Example 11 and 12. 6 is a photograph showing the surface state of the carbon-doped titanium oxide layer obtained in Example 11. FIG. It is a microscope picture which shows the state of the antibacterial product for doctors obtained in Example 13. It is a microscope picture which shows the state of the thin film side surface of the small piece member 3 which the fine pillar which stands on many thin narrow protrusion parts and white pillars which consist of white titanium oxide on the thin film is exposed. A large number of continuous narrow-width projections made of white titanium oxide on the thin film and a large number of continuous narrow-width projections of the small piece member 3 in which fine columns standing on the projection are exposed, and the projections It is the microscope picture which shows the state of the surface of the side where the fine pillar which stands in the side is exposed. It is a microscope picture which shows the state of the layer 2 in which the micro pillar which consists of white titanium oxide stands. It is a graph which shows the result of Test Example 15 (antifouling test). It is a graph which shows the result of Test Example 16 (crystal structure and bonding state). It is a SEM photograph after a heating time of 120 seconds in Example 19. It is a SEM photograph after a heating time of 180 seconds in Example 19. It is a SEM photograph after the heating time of 480 seconds in Example 19.

1 Surface of substrate 2 Fine column 3 Thin film

Claims (7)

The surface of the substrate made of titanium or titanium alloy is heat-treated at a high temperature using a combustion flame of a gas containing hydrocarbon as a main component, or is heated at a high temperature in a combustion gas atmosphere of a gas containing hydrocarbon as a main component. by, at least a portion of the surface layer of the substrate, the carbon is doped in the state of Ti-C bonds, and carbon-doped oxide consisting of titanium oxide or titanium alloy oxide containing 0.3～15At% carbon Antibacterial product for physicians, characterized by a titanium layer. The surface of the substrate made of titanium or titanium alloy is heat-treated at a high temperature using a combustion flame of a gas containing hydrocarbon as a main component, or is heated at a high temperature in a combustion gas atmosphere of a gas containing hydrocarbon as a main component. By doing so, at least a part of the surface layer of the substrate is a carbon-doped titanium oxide layer made of titanium oxide or titanium alloy oxide doped with carbon in a Ti-C bond state and having a Vickers hardness of 300 or more. , Characterized by antibacterial products for physicians. The at least one part of the surface layer of a base | substrate consists of a carbon dope titanium oxide layer which has many protrusion parts which consist of a carbon dope titanium oxide or a titanium alloy oxide, The Claim 1 or 2 characterized by the above-mentioned. Antibacterial product for doctors. At least a portion of the surface layer of the substrate, according to claim 1 or 2, characterized in that, the layer in which fine columns made of titanium oxide or titanium alloy oxide carbon doped is bristled is exposed Antibacterial product for doctors. It is comprised by the layer which consists of carbon-doped titanium oxide or titanium alloy oxide, and a core material, This core material is titanium or a titanium alloy, The one in any one of the Claims 1 thru | or 4 characterized by the above-mentioned. Antibacterial products for doctors listed. It is composed of a layer made of carbon-doped titanium oxide or titanium alloy oxide, an intermediate layer, and a core material, the intermediate layer is titanium or a titanium alloy, and the core material is composed of a material other than titanium or a titanium alloy. The antibacterial product for doctors according to any one of claims 1 to 4 , wherein the antibacterial product is for doctors. A layer of carbon-doped titanium oxide or titanium alloy oxide surface layer is bonded to the underlying titanium or a titanium alloy through a Ti-C bond, any of claims 1 to 6, characterized in that An antibacterial product for physicians according to any one of the above.